1. Field of the Invention
The present invention relates to, for example, a semiconductor device, a display device, a light-emitting device, a driving method thereof, or a manufacturing method thereof. In particular, the present invention relates to, for example, an active matrix liquid crystal display device.
2. Description of the Related Art
With the recent rapid spread of portable information terminals such as smartphones, improvement in their performance has progressed rapidly. Their screens have been increased in size and resolution. In addition to improvement in the resolution of a screen, emphasis has been put on power consumption of a display device. A typical example of the display device is a liquid crystal display device using liquid crystal elements.
Examples of display modes for the liquid crystal display device include a vertical alignment (VA) mode in which liquid crystal molecules with negative dielectric constant anisotropy are aligned vertical to a substrate surface; an in-plane switching (IPS) mode and a fringe field switching (FFS) mode in which liquid crystal molecules with positive or negative dielectric constant anisotropy are aligned horizontal to a substrate surface and a horizontal electric field is applied to a liquid crystal layer.
For example, as an FFS-mode liquid crystal display device, a display device having high-speed response and wide viewing angle is disclosed (see Patent Document 1). The display device includes a first substrate with a first common electrode layer; liquid crystal between the first substrate and a second substrate; and a means for generating an electric field between the first common electrode layer on the first substrate and both a pixel electrode layer and a second common electrode layer on the second substrate so that the display device provides high-speed responses to high input data rates and allows for wide viewing angles for viewers.
Furthermore, as an FFS-mode liquid crystal display device, a liquid crystal display device capable of high-speed response by driving liquid crystal with two pairs of electrodes is disclosed (see Patent Document 2).